This invention relates to a quick disconnect fluid coupling which is made up of mating male and female coupling elements. More particularly, this invention relates to a quick disconnect fluid coupling which is capable of relieving an increase in pressure in a fluid line which incorporates such a coupling by accommodating an increase in the volume of fluid that is retained within the coupling.
In communication and navigation systems for civilian and military aircraft, one or more removable preprogrammed cards are inserted into the system hardware to adequately instruct the hardware in accordance with the intended destination of the flight and/or the mission to be performed by the flight. During the flight a certain amount of heat is generated within each such card by virtue of the resistance heating resulting from electrical current flowing through the electrical elements on the card, and this requires that the card be cooled during its operation. Heretofore, the cooling of the card to prevent an excessive temperature buildup therein has been accomplished partly by radiation cooling and partly by circulating air or other compressible fluid through the card. Removal of heat from such a preprogrammed card by radiation and convection cooling is somewhat limited in capacity, however, and this serves as a limitation on the amount of heat which can be generated within a card to avoid the deleterious effects of excessive temperatures.
It is possible to substantially increase the thermal capacity of a preprogrammed card for an aircraft by utilizing liquid cooling to cool the card during its normal operation. It is possible to substantially increase the thermal capacity of a preprogrammed card for an aircraft by utilizing liquid cooling to cool the card during its normal operation. However, when a card is removed from the system, the pressure of the cooling liquid within the card will increase very substantially as a result of a very small increase in volume, for example, due to an increase in ambient temperature. Thus, an aircraft preprogrammed communication or navigation card should incorporate a pressure relief feature to avoid undesirable and possibly damaging or destructive pressure buildups within the card after the card has been removed from the system. Heretofore, the pressure relief function in each card, as well as the disconnected system, has been performed by a bleeding pressure relief valve located in the quick disconnect fluid coupling that is normally a feature of each card and each liquid cooling system. Previously, however, when the relief valve relieved pressure the fluid relieved would bleed to atmosphere causing liquid to be spilled on the surrounding electronic equipment and contracts.